text: /****************************************************************************
   * libnx/nxmu/nx_eventhandler.c
   *
   *   Copyright (C) 2008-2009, 2011-2013, 2017 Gregory Nutt. All rights reserved.
   *   Author: Gregory Nutt <gnutt@nuttx.org>
   *
   * Redistribution and use in source and binary forms, with or without
   * modification, are permitted provided that the following conditions
   * are met:
   *
   * 1. Redistributions of source code must retain the above copyright
   *    notice, this list of conditions and the following disclaimer.
   * 2. Redistributions in binary form must reproduce the above copyright
   *    notice, this list of conditions and the following disclaimer in
   *    the documentation and/or other materials provided with the
   *    distribution.
   * 3. Neither the name NuttX nor the names of its contributors may be
   *    used to endorse or promote products derived from this software
   *    without specific prior written permission.
   *
   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
   * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
   * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
   * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
   * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
   * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
   * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
   * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
   * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
   * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
   * ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
   * POSSIBILITY OF SUCH DAMAGE.
   *
   ****************************************************************************/
  
  /****************************************************************************
   * Included Files
   ****************************************************************************/
  
  #include <nuttx/config.h>
  
  #include <stdint.h>
  #include <stdlib.h>
  #include <mqueue.h>
  #include <assert.h>
  #include <errno.h>
  #include <debug.h>
  
  #include <nuttx/mqueue.h>
  #include <nuttx/nx/nx.h>
  #include <nuttx/nx/nxbe.h>
  #include <nuttx/nx/nxmu.h>
  
  #include "nxcontext.h"
  
  /****************************************************************************
   * Private Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: nx_connected
   *
   * Description:
   *   The server has completed the connection and is ready.
   *
   ****************************************************************************/
  
  static inline void nx_connected(FAR struct nxfe_conn_s *conn)
  {
    DEBUGASSERT(conn->state == NX_CLISTATE_NOTCONNECTED);
    conn->state = NX_CLISTATE_CONNECTED;
  }
  
  /****************************************************************************
   * Name: nx_disconnected
   ****************************************************************************/
  
  static inline void nx_disconnected(FAR struct nxfe_conn_s *conn)
  {
    /* Close the server and client MQs */
  
    (void)mq_close(conn->cwrmq);
    (void)mq_close(conn->crdmq);
  
    /* And free the client structure */
  
    lib_ufree(conn);
  }
  
  /****************************************************************************
   * Public Functions
   ****************************************************************************/
  
  /****************************************************************************
   * Name: nx_eventhandler
   *
   * Description:
   *   The client code must call this function periodically to process
   *   incoming messages from the server.  If CONFIG_NX_BLOCKING is defined,
   *   then this function not return until a server message is received.
   *
   *   When CONFIG_NX_BLOCKING is not defined, the client must exercise
   *   caution in the looping to assure that it does not eat up all of
   *   the CPU bandwidth calling nx_eventhandler repeatedly.  nx_eventnotify
   *   may be called to get a signal event whenever a new incoming server
   *   event is available.
   *
   * Input Parameters:
   *   handle - the handle returned by nx_connect
   *
   * Return:
   *     OK: No errors occurred.  If CONFIG_NX_BLOCKING is defined, then
   *         one or more server message was processed.
   *  ERROR: An error occurred and errno has been set appropriately.  Of
   *         particular interest, it will return errno == EHOSTDOWN when the
   *         server is disconnected.  After that event, the handle can no
   *         longer be used.
   *
   ****************************************************************************/
  
  int nx_eventhandler(NXHANDLE handle)
  {
    FAR struct nxfe_conn_s *conn = (FAR struct nxfe_conn_s *)handle;
    struct nxsvrmsg_s *msg;
    struct nxbe_window_s *wnd;
    char buffer[NX_MXCLIMSGLEN];
    int nbytes;
  
    /* Get the next message from our incoming message queue */
  
    do
      {
        nbytes = _MQ_RECEIVE(conn->crdmq, buffer, NX_MXCLIMSGLEN, 0);
        if (nbytes < 0)
          {
            int errcode = _MQ_GETERRNO(nbytes);
  
            /* EINTR is not an error.  The wait was interrupted by a signal and
             * we just need to try reading again.
             */
  
            if (errcode != EINTR)
              {
                if (errcode == EAGAIN)
                  {
                    /* EAGAIN is not an error.  It occurs because the MQ is opened with
                     * O_NONBLOCK and there is no message available now.
                     */
  
                    return OK;
                  }
                else
                  {
                    gerr("ERROR: _MQ_RECEIVE failed: %d\n", errcode);
                    _MQ_SETERRNO(nbytes);
                    return ERROR;
                  }
              }
          }
      }
    while (nbytes < 0);
  
    DEBUGASSERT(nbytes >= sizeof(struct nxclimsg_s));
  
    /* Dispatch the message appropriately */
  
    msg = (struct nxsvrmsg_s *)buffer;
    ginfo("Received msgid=%d\n", msg->msgid);
    switch (msg->msgid)
      {
      case NX_CLIMSG_CONNECTED:
        nx_connected(conn);
        break;
  
      case NX_CLIMSG_DISCONNECTED:
        nx_disconnected(conn);
        set_errno(EHOSTDOWN);
        return ERROR;
  
      case NX_CLIMSG_REDRAW:
        {
          FAR struct nxclimsg_redraw_s *redraw = (FAR struct nxclimsg_redraw_s *)buffer;
          wnd = redraw->wnd;
          DEBUGASSERT(wnd);
          if (wnd->cb->redraw)
            {
              wnd->cb->redraw((NXWINDOW)wnd, &redraw->rect, redraw->more, wnd->arg);
            }
        }
        break;
  
      case NX_CLIMSG_NEWPOSITION:
        {
          FAR struct nxclimsg_newposition_s *postn = (FAR struct nxclimsg_newposition_s *)buffer;
          wnd = postn->wnd;
          DEBUGASSERT(wnd);
          if (wnd->cb->position)
            {
              wnd->cb->position((NXWINDOW)wnd, &postn->size, &postn->pos, &postn->bounds, wnd->arg);
            }
        }
        break;
  
  #ifdef CONFIG_NX_XYINPUT
      case NX_CLIMSG_MOUSEIN:
        {
          FAR struct nxclimsg_mousein_s *mouse = (FAR struct nxclimsg_mousein_s *)buffer;
          wnd = mouse->wnd;
          DEBUGASSERT(wnd);
          if (wnd->cb->mousein)
            {
              wnd->cb->mousein((NXWINDOW)wnd, &mouse->pos, mouse->buttons, wnd->arg);
            }
          }
        break;
  #endif
  
  #ifdef CONFIG_NX_KBD
      case NX_CLIMSG_KBDIN:
        {
          FAR struct nxclimsg_kbdin_s *kbd = (FAR struct nxclimsg_kbdin_s *)buffer;
          wnd = kbd->wnd;
          DEBUGASSERT(wnd);
          if (wnd->cb->kbdin)
            {
              wnd->cb->kbdin((NXWINDOW)wnd, kbd->nch, kbd->ch, wnd->arg);
            }
          }
        break;
  #endif
  
      case NX_CLIMSG_BLOCKED:
        {
          FAR struct nxclimsg_blocked_s *blocked = (FAR struct nxclimsg_blocked_s *)buffer;
          wnd = blocked->wnd;
          DEBUGASSERT(wnd);
          if (wnd->cb->blocked)
            {
              wnd->cb->blocked((NXWINDOW)wnd, wnd->arg, blocked->arg);
            }
          }
        break;
  
      default:
        gerr("ERROR: Unrecognized message opcode: %d\n",
             ((FAR struct nxsvrmsg_s *)buffer)->msgid);
        break;
      }
  
    return OK;
  }
  